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arXiv · 1710.09129

Under-liquid Self-Assembly of Submerged Buoyant Polymer Particles

Abstract

The self-assembly of submerged cold-plasma-treated polyethylene beads is reported. The plasma-treated immersed millimetrically-sized polyethylene beads formed well-ordered 2D quasi-crystalline structures. The submerged floating of light polyethylene beads is possible due to the energy gain achieved by the wetting of the high-energy plasma-treated polymer surface prevailing over the energy loss due to the upward climb of the liquid over the beads. The capillary immersion attraction force is responsible for the observed self-assembly. The observed 2D quasi-crystalline structures demonstrate dislocations and point defects. Mechanical vibration of self-assembled rafts built of polyethylene beads leads to the healing of point defects. The immersion capillary lateral force governs the self-assembly, whereas the elastic force is responsible for the repulsion of polymer beads.

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Victor Multanen, Roman Pogreb, Yelena Bormashenko, Evgeny Shulzinger, Gene Whyman, Mark Frenkel, Edward Bormashenko. 2017-10-25. Under-liquid Self-Assembly of Submerged Buoyant Polymer Particles. https://doi.org/10.1021/acs.langmuir.6b00636

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